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The atomic number is the number of protons in an atom.The mass number is the sum of protons & neutrons in an atom.
Mass number (written at the left side above the symbol is 16) No. of neutrons = 16 – 8 = 8 Nitrogen Atomic number = no. of protons = 7 Mass number = protons + neutrons = 14 Number of neutrons = 14 - 7 = 7 Complete the following table:
An atom is electrically neutral because the number of protons = the number of electrons. The positive charge of the proton is opposite to that of the electrons. Electrons revolve around the nucleus in orbits called energy levels. a. b. There are 7 energy levels represented from the nearest to the nucleus to the farthest by the letters K, L, M, N, O , P, Q . c. The energy of the level increases by the increase of the distance from the nucleus. d. Each level is saturated (completely filled) with a certain number of electrons. e.The number of electros which saturate energy levels 1-4 is calculated by the rule 2n2 Where n is the number of the energy level.
f. g. The excited atom loses the quantum of energy & electrons return to the original level (ground state) Distributing electrons in energy levels electronic configuration.
Complete the following table:
Date: 2015-12-24; view: 965
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